O,O-dialkyl phosphoroamidothioates are intermediates used in the preparation of phosphoroamidothioate insecticides. In particular, O,O-dimethyl phosphoroamidothioate is an intermediate which is required in producing O,S-dimethyl phosphoroamidothioate. O,O-dimethyl phosphoroamidothioate is generally produced by reacting O,O-dimethyl phosphorochloridothioate with two equivalents of aqueous ammonia with or without a solvent. U.S. Pat. No. 3,309,266 discloses that O,O-dimethyl chlorophosphorothioate is reacted with ammonia or a primary alkylamine to produce O,O-dimethyl phosphoroamidothioate. In a manner similar to the method disclosed in U.S. Pat. No. 3,309,266, U.S. Pat. No. 3,639,547 discloses that O,O-dimethyl phosphoroamidothioate can be made via ammoniation of an O,O-dimethyl halophosphorothioate. With the above methods, the yield of the formed O,O-dimethyl phosphoroamidothioate is low, and the purification process, requiring ammonia recovery, is extensive. Thus, there continues to be a need in the art, for an efficient method for making O,O-dimethyl phosphoroamidothioate with an increased net yield, and preferably, without the need for an ammonia recovery procedure.